1. Field of the Invention
The present invention relates to a truss system. And more particularly, the present invention relates to a foldable and collapsible truss system which can be assembled at the construction situs and, after use, be collapsed and folded and moved conveniently, in component sections, from such situs.
2. General Background
Various truss systems are known for use in building construction. The building of trusses on a building site is an expensive and time consuming operation. Because of this, the building industry has adopted prefabricated trusses which eliminate costly on-site labor time. When prefabricated trusses are completely assembled, they are shipped to the job site for use but, due to their size, often require an inordinate amount of shipping carriers and thus time and expense. Furthermore, because prefabricated trusses must be ordered to size for each individual structure, the transportation reliability factor is greatly reduced.
Several attempts have been made in the prior art to develop a truss system which is collapsible, foldable and easily transportable in quantity in the collapsed state and, upon arrival at the construction site, adapted to be erected in a short period of time.
U.S. Pat. No. 3,760,550, issued to W. E. Mueller, et al., discloses a truss structure prefabricated and capable of being shipped in a collapsed condition and which can be erected easily at the site into a roof truss while maintaining a desired and predetermined roof pitch.
U.S. Pat. No. 2,642,825, issued to C. A. McElhone, et al., and discloses a foldable and compactable roof truss having a plurality of upper chords hingedly connected at the truss peak, the upper chords being hingedly connected at their truss ends to the truss ends of each of a plurality of bottom chords connected at the center of the truss span. There are further provided compression members and tension members hingedly connected to both the top and bottom chords.
U.S. Pat. No. 2,386,077, issued to C. B. K. Van Norman, also discloses a collapsible roof truss.
U.S. Pat. No. 3,873,573, issued to D. H. Vaughan, and discloses a three-dimensional triangulated truss capable of being retracted to a compact package for storage and shipment and then expanded on site for erection and connection to similar modules.
Other prior art patents exist which show truss systems which are not foldable and collapsible but which attempt to provide adaptability for various construction requirements:
U.S. Pat. No. 3,826,057, issued to J. W. Franklin discloses chords, struts, couplers, connectors and brace components for cooperative interconnection to provide trusses of various lengths, heights and inclinations with fastener elements used at selected positions to provide desired adaptability.
U.S. Pat. No. 3,078,970, issued to R. S. Black, and discloses a truss-type joist longtitudinally adjustable to vary the length thereof by providing overlapping longitudinal sections with bolt holes spaced apart in series for adjustment to elongate or contract the joist according to the span required.
U.S. Pat. No. 3,977,536, issued to S. T. Moore et al., and discloses the conventional "flying" truss deck form.
U.S. Pat. Nos. 4,102,096; 4,102,108; and 4,106,256 all issued to D. L. Cody, and disclose an expandable truss structure and a wide variety of applications of the same.
U.S. Pat. No. 3,966,164, issued to S. S. Dashew, discloses an adjustable truss support.
U.S. Pat. No. 1,376,990, issued to W. F. Zabriskie, discloses a collapsible truss-like structure for reinforced concrete construction.
U.S. Pat. No. 1,458,866, issued to C. H. Wetzel, discloses a collapsible and foldable truss-like structure.
U.S. Pat. No. 3,638,373, issued to G. Chapaman and U.S. Pat. No. 3,605,355, issued to B. J. Solesbee, disclose collapsible roof trusses.
The following U.S. Patents disclose known art pertinent to the field of the invention:
U.S. Pat. No. 3,942,618, issued to J. W. Franklin.
U.S. Pat. No. 1,141,385, issued to J. O. Ellinger.
U.S. Pat. No. 4,237,869, issued to F. H. Rooney.
U.S. Pat. No. 3,564,783, issued to S. B. Dunne.
Further prior art which is known to the applicant but not the subject of a U.S. Patent is an aluminum truss system marketed under the trademark SYMONS. Catalogs illustrating the SYMONS truss system are enclosed as Exhibits A and B.
Many of these truss systems suffer in that they are bulky in the collapsed state and have a complex structure requiring extensive time and effort to re-assemble the truss from its collapsed state. Some of the patented devices require a voluminous amount of pins and fasteners to interconnect component parts which can be lost or misplaced when the assembly is in the collapsed condition. Other devices, when collapsed, may be compact but in only one dimension thus leaving a large width, length or height as the case may be.
Therefore, it is as an object of the present invention to provide a truss system which is collapsible and compactable to a size allowing for ease of shipment in quantity.
It is a further object of the present invention to provide a collapsible and compactable truss system which can be expanded and assembled in a minimum amount of time.
It is a further object of the present invention to provided a collapsible and compactable truss system having a minimum amount of removable fasteners and spacers.
It is a further object of the present invention to provide a collapsible and compactable truss system which maintains its structural integrity and strength in the assembled position.